Zudi Lu is Professor
within Mathematical Sciences at the University of Southampton. Prof
Zudi LU joined, as a Professor/Chair in Statistics, in Mathematical
Sciences Academic Unit and Southampton Statistical Sciences Research
Institute (S3RI) at University of Southampton, UK, in late 2013.
Prior to that, he had worked at several international academic
institutions, including the University of Adelaide (2009-2013) and
Curtin University (2006-2009) in Australia, the London School of
Economics (2003-2006) in the UK, the Academy of Mathematics and
Systems Science (1997-2003) in Beijing, China, and the Universite
Catholique de Louvain (1996-1997) in Louvain-la-Neuve, Belgium,
after he received his PhD degree from the Chinese Academy of
Sciences in 1996. He was a recipient of the Australian Research
Council Future Fellowship in its 2010 round, and is an elected
member of the International Statistical Institute.
TITLE OF TALK: Semiparametric Model Averaging for Dynamic
Time Series Forecasting: Methodology and Application
ABSTRACT: In this talk I will review some recent
progress on semiparametric model averaging schemes for nonlinear
dynamic time series regression models with a very large number of
covariates including exogenous regressors and autoregressive lags.
Our objective is to obtain more accurate estimates and forecasts of
time series by using a large number of conditioning information
variables in a nonparametric way. We (my coauthors including Jia
Chen, Degui Li and Oliver Linton) have proposed several
semiparametric penalized methods of Model Averaging MArginal
Regression (MAMAR) for the regressors and autoregressors either
through an initial screening procedure to screen out the regressors
whose marginal contributions are not significant in estimating the
joint multivariate regression function or by imposing an approximate
factor modelling structure on the ultrahigh dimensional exogenous
regressors with principal component analysis used to estimate the
latent common factors. In either case, we construct the optimal
combination of the significant marginal regression and
autoregression functions to approximate the objective joint
multivariate regression function. Asymptotic properties for these
schemes are derived under some regularity conditions. Empirical
applications of the proposed methodology to forecasting the economic
risk, such as inflation risk in the UK, will be demonstrated.